• When the noun (object) begins with a vowel, whether or not it is feminine, the masculine form of the possessive pronoun is used for je, tu, and il/elle/on.

A common example of this is the word friend. Ami (masculine) and amie (feminine) are both preceded by mon, ton, and son because of the beginning vowel in ami.
e.g. mon/ton/son amie = my/your/his/her/one's female friend.

• It is the same for words beginning with h.
e.g. histoire - story.
One would say mon histoire, ton histoire, son histoire, instead of using the feminine possessive pronouns (ma, ta, sa).

Get French lessons and verbs emailed direct to you free

Get lots of useful French lessons and French verbs sent to you each week free by email, from the 200 Words a Day accelerated language learning team. Great for learning, review and consolidating your French knowledge.